LIQUID-CRYSTALLINE POLYMERS - FROM SELF-ORGANIZATION TO FUNCTIONS ANDAPPLICATIONS

Liquid crystals derive their unusual properties and their broad range of applications from their unique spatial and orientational order givi ng rise to specific symmetries, to strong anisotropies with respect to macroscopical properties and to a strong coupling to external fields. We have studied for liquid crystalline polymers modes of inducing str ong modifications of the anisotropic optical properties locally in sol id films by light. A storage process is described in this contribution which is based on light-induced trans-cis-trans-isomerization reactio ns of azobenzene chromophores attached to a polymer backbone as side g roups in liquid crystalline polymers. The chromophores are able to rot ate in the glassy state if subjected to linearly polarized light: the azobenzene units approach a saturation orientation which is perpendicu lar to the polarization direction of the light. The contribution discu sses the molecular mechanism of this process as well as possible appli cations.